Detecting and minimizing RF breakdown on microfabricated surface ion traps*

RF breakdown is a major limiting factor in the maximum RF voltage microfabricated surface ion traps can sustain.  The complicated physics involved in breakdown makes it difficult to predict a priori how susceptible new trap designs will be to this destructive process.  We have developed two techniques for detecting RF breakdown events in situ, one using free-space RF field detectors, and the other monitoring the back-reflected RF signal from the trap itself. Here we describe these techniques and share the results of an extended study of RF breakdown on many different traps.  Our results highlight the danger of ramping up the RF voltage too quickly for the initial use of a new trap.  We present a procedure for safely turning on new traps, by increasing the voltage slowly and monitoring for breakdown.  Also, we briefly describe our most recent fabrication efforts to mitigate breakdown in future traps.